Alloy and material employing the same



. torch. It has ratented May 1, 1928.

UNITED STATES,

JOSEBH G. DONALDSON AND HENRY GUARDIAN METALS COMPANY, OF WARE.

lio m'awing.

Our invention, although not limited thereto, concerns more particularly material, such as safe and vault plates and the like, adapted to resist attack by the local application of high. heat, as by means of the oxy-acetylene long been known that copper, because of its high heat conductivit and the fact that it cannot be out by oxidation, offers {substantial resistance to penetration by means of high heat locally applied. It has been found defective, however, for the reason that its melting point'is relativelylowand also because it flows freely when it has been brought to a melting temperature. We

have found a way to raise the melting point.

. of copper and, at the same time, preserve or approximately I increase its high addition profoundly heat conductivity and also to produce a'material which does not flow when brought to a melting temperature as by the local application of high heat, We accomplish these results by the addition to copper of relatively small amounts of silicon and carbon, it-having been found that such affects the physical qualities ,of the copper, producing a' material having the characteristics above stated. A typical formula of such an alloy would be i as follows, disregarding the impurities commonly found in refined copis first made molten,

per, such as small amounts of iron, lead and tin which may be present without serious detriment,thereto:,

' Percent.

.60 to .75 .015 to .020 99.385 to 99.230

In carrying out our. invention, the copper preferably in a direct-' arc type electric furnace. If other means are employed formelting, then carbon should be added to the melting, thereby assisting in the process of copperduring the time of the deoxidation thereof..- If the metal is heated ,ina direct-arc type electric furnace, then it is not necessary to add a separate portion of carbon to the mixture, ,inasmuch as this in gradient will be furnishediby the drippings from the electrodes.- Afte'r-th'e metal has from 2 to 2l/ by weightof 30% cupro- Application filed May 19,

not be cut by the alloy inother metal,

these are impenetrable en brought'to a high'heat, we add thereto "\AJCili will u tU-Utzl L. COLES, OF HAMILTON, OHIO, ASSIGNORS TO HAMILTON, OHIO, A CORPORATION OF DELA- ALLOY AND MATERIAL EMPLOYING- THE SAME.

1923. Serial No. 640,226.

silicon in powdered form. The alloying takes place very quickly with much loss or' heat and a not-able chan e takes place in the color of the molten meta It is necessary to stir the metal rapidly; otherwise, this alloying will be largely a and the surface of the molten bathwill tend to freeze. After the metals are thoroughly mixed, the alloy can be poured in the regular way, as by means of a ladle. As an alternative, the cupro-silicon can be made molten and can be mixed with the copper while the latter-is either in the furnace or the ladle.

The resulting alloy resists best when the silicon content is from .60 to .75%. If greater 'or less amounts of silicon are added, there is a notable change in the resistance of the metal. If too great an amount of silicon is added, comes less than that of copper.

In a previous application we have described material characterized by a core having a high-melting point encompassed by another metal, termed by us the sheath P'ATENT A OFFICE.

surface phenomenon then the resistance of. the alloy be- 4 tivity. The alloy disclosed above makes an excellent sheath metal, inasmuch as it canoxidation and yields very slowly when extremely high heat is locally applied. As pointed out above, this alloy will'not flow when,'raised above its melting point but appears to slowl slough off in very small flakes. I

Another method of utilizing this alloy is to usethe same as a core and to encompass such as cast iron, steel and the like. Here the core and sheath will be rigidly united, the areas in contact being, in act, alloys of the core and sheath materials. On account of its very high heat conductivit and its other pecullar proper ties,-it has been found that such a core will resist prolonged attacks by means of the oxy-' acetylene torch. The encompassing of this alloy in another metal permits its use in much thinner strata. Tests have shown that to the torch, notwithstanding the factthat the same thickness of the alloy not so encompassed is penetrated It hasalso been found with relative .ture.

be melted when attacked by means of the largest size torches. The cast iron will ab that an alloy of copper. and silicon is superior to copper and other non-ferrous'metals when used either as a .sheath metal'as described above, or as a core encompassed by other metals.

When using the alloy herein described a'core, we may combine another metal (as cast-iron) therewith and then encompass the whole 1n a suitable sheath metal such as steel. In such case, the alloyv may form from to 30 per cent of the core.

So-called torch-resisting plates have herea tofore been suggested in which copper and cast iron in varied proportions have been combined. The best results can be obtained -in such plates when the copper content is approximately to of the entire mix- Plates so constructed, however, may

sprb only about 5% of the copper and the remaining copper is, therefore, unequally distributed throughout the mass, the cast iron constituting the matrix in which the excess copper is embedded. Our new :alloy,

however,employed, as above. stated, greatly increases the resistance of the plate to attack in the forms here-in suggested.

Having now described our invention, what .we claim and desire to secure by Letters Patent is as follows 1. A compound plate consisting of a core which is an alloy of 99.3859 9.230% copper, .01'-.020%- carbon and 50-35% silicon,

said corebeing encompassed by other metal and united thereto as by alloying therewith.

2. new article of manufacture being the combination of a plate of an alloy of a majorityportion of copper, carbon, and silicon between ,60.7 5%, which alloy may be penetrated by a torch when taken alone, and a high melting point metal joined to said -al-- 10y plate to form a compound plate that is not penetrable by the torch.

3.;A substantially integral metallic structure, comprising aFmetalhaving a high melting point, and an alloy of copper, lessjth'an 75% silicon and less'than .O15% carbon,

signed this 16' day of 55. 

